Since you need more advanced features to keep up with your business's growth, you can upgrade to QuickBooks Online (QBO) from QuickBooks Self-employed (QBSE). I'll gladly share more details about this below.
QBSE is the version of QuickBooks for self-employed individuals that helps record self-employed income and expenses, track mileage, and prepare your Schedule C tax form. While QBO is a financial management software specifically designed for small businesses to help manage sales and income (includes the sales tax feature to track taxable sales option) and financial data. To see which plan is right for you, you can check out this page: QuickBooks plans for every kind of business.
Once you're ready to switch from QBSE to QBO, you may want to see this article for the step-by-step guide: Switch from QuickBooks Self-Employed to QuickBooks Online.
If you have other concerns about which version of QuickBooks is right for your business, please don't hesitate to let me know in the comments below. I'm always ready to help. Enjoy the rest of the day!